Microsoft Access 2010 Bible

Chapter 2: Creating Access Tables

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field description can help clarify a field whose purpose is ambiguous or give the user a more com-

plete explanation of the appropriate values for the field during data entry.

Creating tblCustomers

Working with the different data types, you should be ready to create the final working copy of

tblCustomers. When creating the table, you must add a field that is used to link this table to

two other tables (tblSales and tblContactLog) in the Collectible Mini Cars application.

Using AutoNumber fields

Access gives special considerations to AutoNumber fields. You can’t change a previously defined

field from another type to AutoNumber if any data has been added to the table. If you try to

change an existing field an AutoNumber, you’ll see an error that says

Once you enter data in a table, you can’t change the data type of

any field to AutoNumber, even if you haven’t yet added data to

that field.

You’ll have to add a new AutoNumber field and begin working with it instead of changing an

existing field to AutoNumber.

Note
Only one AutoNumber field can be added to an Access table. Generally speaking, it’s better to use
AutoNumber fields where their special characteristics are needed by an application.

Completing tblCustomers

With tblCustomers in Design view, you’re ready to finalize its design. Table 2.1, shown earlier

in this chapter, lists the field definitions for tblCustomers. Enter the field names and data types

as shown in Table 2.1. The next few pages explain how to change existing fields (which includes

rearranging the field order, changing a field name, and deleting a field).

Here are the steps for adding fields to a table structure:

1. Place the cursor in the Field Name column in the row where you want the field to
   appear.


2. Enter the field name and press Enter or Tab to move to the Data Type column.


3. Select the field’s data type from the drop-down list in the Data Type column.


4. If desired, add a description for the field in the Description column.

Repeat each of these steps to create each of the data entry fields for tblCustomers. You can press

the down-arrow (↓) key to move between rows, or use the mouse and click on any row. Pressing F6

switches the focus from the top to the bottom of the table design window, and vice versa.